Automatic electric generating unit



w. w. BUCHER.. AUTOMATIC ELECTRIC GENERAUNG UNH.

APPLICATION FILED MARY 20. I9I9. v

Patented July 4, 1922.

2 SHEETS-SHEET I.

bgg-

UNITED .STATESy PATENT OFFICE.`

WILLIAM W. BCHER, 0F CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,TO KOHLER COMPANY, 0E KOHLER, WISCONSIN, A CORPORATION OF WISCONSIN.

AUTOMATIC ELECTRIC GENERATING UNIT,

Specification of Letters Patent. Patentedl July 4, 1922.

Applicationmed March 2o, 191s. swarm. 283,910.

To all who/m, t may cof/wem:

Be it known that WILLIAM W. BCHER, citizen of the United States,residing at Chicago, in the county ot' Cook and State of Illinois, hasinvented certain new and useful Improvements in Automatic ElectricGenerating Units, of Which the following is;

a speciiication. y

My invention relates to improvements in self contained automaticelectric generating units and it consists more especially of thefeatures hereinafter pointed out in the annexed claims.

Some of the purposes ot my invention are (l) to provide an entirelyautomatic electric generating unit which supplies current at a normalcommercial voltage adaptable to standard accessories Without thenecessity of using many cells of storage battery; lthat is self startingwithout the use of a separate starter; (3) that eliminates the use oflarge capacity sto-rage cells; (4) that employs a low voltage `currentmomentarily onA highl voltage service mains to automatically start thesystem by utilizing` the shunt coil and armature only of a. compoundWound generator of standard voltage rating to cause such generator to`act as a motor and thus start the system; (5) that automaticallycontrols the speed of the engine according to thel fluctuations of loadby the manipulation of the eny gine throttle and choker simultaneously;and

(6) that automatically through the intermediary of a governor actuatedby the. engine, or by any other means, prevents the generator remainingat low voltage after having been subjected to a low voltage currentWhile being used as a motor to start the engine.

lVith. these and other ends in view I illustrate in the accompanyingdrawings such instances of adaptation as will disclose the broadunderlying principles Without limiting myself to the specific detailsshown.

Fig. l is a side elevation, from a. photo graph, of a completeself-contained generating unit as employed in actualpractice.

Fig. 2 is a diagrammatic View of the stopare also shown in dotted lines.

second stages of a start-ing operation. In

this figure the circuits which are not in use Fig. 5 is also adiagrammatic view similar to Fig. 2, showing the third stage ofstarting, the dead circuits being also desige nated by dotted lines, asin the other gures.

F ig. 6 is a diagrammatic view of the full running relation ot theseveral parts of a complete system, inactive lines being shown by meansof dotted lines.

As several fea-tures of this invention are made the subject of separateapplications, notably, (1) the .control switch 8; (2) the duplex magnet28; and (3) the governor 20 in relation to the throttle and chokercontrol, these will not be described in great detail, except in so faras cooperating features are necessary to a. clear understanding of thepurpose andthe basically essential parts of my present system. In otherapplications I have disclosed earlier stages of development Whichhowever do not speciallyl relate to the present disclosure, except as tothe broad general ground hereafter referred to. Several improvementswhich have been made under the exacting demands of actual practice havestill further matured the basic ground of these inventions. This ground,among other features, broadly covers a generator of normal high voltagerating, an internal combustion engine for operating the generator, anignition system for the engine, a. low voltage battery, high voltageservice mains, and automatic switching means responsive to the minimumpractical demand for current on such mains or to a discontinuance ofsuch demand.

It also comprises a system which is adapted to temporarily use the lowvoltage battery current on the vhigh voltage service i mains, theiraccessories, the switch and the high voltage generator to start thesystem automatically,vand further to stop the" engine andthe system whenthe demand for current on the service mains ceases.

A further broad purpose, more concisely stated comprises the followingfeatures to temporarily use anormal high voltage generatorfconnected toan internal combustion engine-for starting purposes on current from a.low voltage battery, to innnediately thereafter have the generatordeliver high voltage current as needed to supply standard voltage.accessories.

Prior efforts in this field have essayed the use of a double endedarmature in the gen-` erator, one end for a low voltage starting currentand the other end for a high voltage service current. Such a proposal isembodied in my Patent No. 1,332,707, dated March 2, 1920. Under thatplan the generator must. be of a special type, making its cost nearlydouble that of one whose armature is standard throughout..

lllhether one or the other type of generator is used is immaterial, asthe broad principle of temporarily using a low voltage current on normalhigh voltage service mains to set the plant in operation applies toeither of the types, or to those in which a separate low voltage starteris used. This ground has been disclosed in practicahtests antecedent tothis application.

A differentiating factor which clearly sets this invention apart fromother efl'orts disclosed in the prior art` in which compressed aircooperating means have been used, or a battery of the saine voltage asthe service voltage of the generator has been employed, is found in theexisting current limitation of a single high voltage lamp when subjectedto a fractional part of its normal voltage rating, and the inclusion ofa control responsive to such limited current by which an electricgenerating system is set into operation to subsequently supply currentto the high voltage accessories at their normal rating, regardless ofthe specific type of generator that may be used.

Such a system forms the nucleus around which my several relatedinventions have been developed, and whatever degree of specializationhas been attained the fnndamental features play an important role ineach of the developing stages.

The terms. high. normal, or standard voltage, for the purpose of thisdescription, designate approximately lll) and il?) volts; and, the term.loiv voltage. for a similar purpose. may mean l volts. or t3 volts, orany practical voltage necessitating the use of va minimum number ofcells to complete each starting operation.

lf'or the purpose of this exemplification, the system comprises a selfcorta-ined unit. without a switch board or other extraneous cooperatingdevices. ln installing the same,

all that is necessary is to connect the terminals of the generator toexisting service mains. connect the cooling system if separatelysupplied, turn on one of the usual such mains and, in an @ii-- mannerthe system ivill at lamps found on tirely automatic once supply currentto one or more lamps, ctc., up to its full capacity as long as desiredand the fuel is fed to the engine. regardless how frequently orinfrequently the plant is started and stopped.

'llie engine l supports the generator 2, the governor 2U, the vacuumfuel feeding system 22, the battery charging resistance 25, and it mayalso support the battery 2G on a suitable projecting shelf. If thebattery 26 is not so suppoited it may be placed on the floor anywhereconveniently adjacent the dynamo ln anyevent its socket terminals, notshown. are simply attached to suitable. plug terminals on the switch tlwithout regard to their polarity, as in practice it has been found`immaterial in what relation the battery is connected.

Generator 2 is provided with the usual end-ring bearing bracket Il. Atits other end, next the engine, a supporting spider 4 placed. This isattached to the generator and a casting 5 which encloses the fiy wheelG. This casting is secured to the base of the engine as shown in Fig. l.The engine shaft 7. is also the armature shaft, yet in practice it isusual to have tivo separate shafts joined by an insulating coupling.Above the generator 2 a switch unit 8 is placed.

This switch 8 includes all the operating controls of the electrical partof the system and dispenses with the usual separate sivitch hoard. ltcarries a starting magnet 47 and a ruiming magnet lf3, only showndiagramiiiatically in Fig. Q. etc.. and it also supports a duplex magnetQS-G This duplex magnet comprises a fine wire battery starb ing controlcoil 63 and a coarse wire dynamo ruiming control coil 28. The hat-tery2li. resist-ance magneto 2l, and thc governor control QT are the onlyexternal connections from the sivitch, hut as these are all made inadvance in completed plants the pur chaser does not need to givc anyattention to them whatever.

'lhe engine is s-:iqiplicd with a carburetor fl and a throttle l!)controls the fuel in the inlet passage 2l. fi choker ll controls theadmission of air to the 'arhureteix 'lhc throttle lll and the choker 1lare rcspctively controlled by the governor by links l2 and lilconcia-ind to arm let. This arm is pivoted at l5 and a short extensionllY cooperates with a dash pot lo to prevent "hunting" Another extensionla cai-ries a weight l?) to counter halanci,l the lever system. Such aspeed control for widely varying loads might he inelliclenil); uhstituted by a voltager coil controlled h. thli dynamo. but it is believedto be much ic:-V dependable than a governor in the handsA of users whoare not electricians. Such a substitute would be subject to variablemovew ment which in the very nat-ure of things more diicult to controlthan a connected mechanical speed element. In all of the magnets used inthis system variable movement is not used, but instead positive extremesof movement are employed.

The engine spark plugs 23 are served by the magneto 21 over line 79, inany Well known manner, and the cylinder walls are cooled in the usualway b a circulating water system, not shown. The generator 2 is of thecompound type, having a series coil 53 and a shunt coil 55. If furthercompensation is required tor any reason it may be overcompounded bywinding 54. Terminals 52 and 56 of the generator serve as outsideconnections to the switch 8 and battery 26. trom the `series coil 53 tothe switch.

lVithout going into. further details the operation of the system will bereadily followed from the subsequent description. f In Fig. 2. thestopping relation is shown, in which all the inactive circuits aredesignated by dotted lines and the one active circuit-the magneto groundconnection 71 as a full line. Fig. 3 shows a definite short circuiting,or cutting out of coil 63 as soon as the high voltage of the dynamocomes on, to use the series coil 28 as a protection to 63. In Fig. 2these coils are shown in parallel connection. Either expedient, or anyalternative, will protect the coil 63 from injury.

The first step in starting is to turn on one or more lamps 50, etc., bymeans of any suitable switches 49. This connects the two service mains59 and 60 through a very high resistance, if a single lamp is turned on,to the low voltage battery 26. In consequence ot the total resistance ofthe circuit being high a very small amperage `current will flow over it.This means that the coil 63 must be quite sensitive and its moving partsvery responsive in order to control the other parts of the systemwithout failures.

This first step causesv current to iow 'through coil 63 to energize itand shift the bar 38, either through a solenoid acting on a movable corewithin fixed limits, or otherwise.. In any event the movement is apositive one being limited in both directions without any intermediarypositions whatever. The raising of bar 38 from off lower contacts 36 and37 trees the primary'77 of magneto 21 of its short circuit over line 71grounded at 81 and rThis leaves the secondary 78 *ice to supply currentto the spark plugs 23 over line 79 which is grounded at 80.

The circuit of this initial starting control current may be traced byfollowing the full lines shown in Fig. 4, from the battery 26, pastjunction 29. line 61, past junction 30 to lower contact 31 of theiunning magnet 43, over the bar 39.` onto pigtail 32, line 62 to coil63, thence past junction 48, onto A separate connection 67 leadslestablished.

service main 59, switch 49, lamp 50, service main 60 to junction 51,line 64 to junction 52 and thence by line 65 back to the battery.

The next starting step is to energize the starting magnet 47. This isdone by magnet 63 moving the bar 38 to its extreme upward position Whereit connects contacts 34 and 35. This places the starting magnet 47 incircuit with the battery 26 over the following line, Fig. 4. In tracingthis line it is well to again start Jfrom the battery 26, passingjunction 29, over line 61, past junction 30 to contact 31, bar 39 tocontact 33, line 7 6, to governor control 27 and back over line to uppercontact 34, bar 38, contact 35; to starting magnet 47 over line 70; line74, past junction 57 to line 72, past junctions 51 and 52 on line 64;thence back to the battery over line 65.

The third stage, shown in Fig. 5 follows the first two so rapidly that,to all appear'- ances the results occur at the same moment. This stageis controlled by the starting magnet 47 which brings its bar 44 againstcontacts 45 and 46 to close ay circuit from the battery 26 to thegenerator 2, to set the engine in operation. The heavy current on thiscircuit leaves the positive side of the battery 26, passing junction 29on line 61. branching olli' at junction 30 to reach contact 46, thenceover bar 44, contact 45, line 68 to dynamo terminal 56, from Whe-re onlythe armature and shunt field 55 are traversed, joining at 52 to returnto the battery over 65. v

The system is now in operation. The heavy battery current has used thedynamo as a motor to start the engine which is supplied with ignitioncurrent from theV magneto 21, shown in Fig. 5. It should be rep'atedthat the series field 53 has not been used so far in the startingoperation, but dependence has been placed entirely on the armature andthe shunt field 55 of the dy namo.

As soon as the dynamo 2 operates at its rated voltage, after thegovernor 2O has opened circuit 75 and 76 at 27, Fig. 6, running magnet43 comes into action through current supplied by the dynamo,independently of any Contact bars, etc., Whatever. It is connected at 57to line 72, junction 51, line 64, and terminal 52 of the generator 2.The other side of the circuit leads trom the magnet to junction 58 ofline 67, thence over the series field 53 of the dynamo to the otherdynamo terminal 56. i

The energizing of running magnet 43 shifts bar 39 from off the lowercontacts 31 and 33 tothe upper contacts 40, 41 and 42 and the runningcircuit shown in Fig. 6 is Vproceeding through series coil 53, line 67to junction 58, contact 40, bar 39, contact 41,

In tracing this circuit a startline 69 to the running contro magnet Q8,where the presence of its current ctiect causes the magnet to continueto hold bar 8S raised, regardless of load fluctuations, so as to keepthe system in operation by not permitting the magneto to becomegrounded. From the. magnet 28 it leads through service line 59, closedswitches l), lamps 50, or other accessories, to the returning servicemain GO, past junction 5l to line (54 and the other terminal ot' thegenerator armature and shunt iield 55.

At the same time that the generator i2 is supplying service mains 59 andt3() with high voltage current it is also automatically recharging thebattery 26 over the following circuit which is simply identiied bysuccessive numerals, without naming the lines or junctions. Fromterminal 5G, touching 53. GT, 4 0. 39, 42, T3, resistance 25. 66, 29,battery 26. (S5, and 52 back to the generator.

.As shown inFig. (i, current from the dynamo at high voltage divides onbar 39, anextremely small part going over pigtail 32, line (52 to magnet(i3, rejoining the heavy current that branched oil' at contact il ontoline (59 and magnet 2S, at 48 leading to the service main 59. Because ofthis connection and the relative resistances ot the coils t28 and 63being ot the order .O75 to 445 respectively, practically all current iscut ott from coil .63, thus protecting it against the injurious effectsot' overheating without using any contacts that are subject to arcing aswould be the case if a direct cut out was employed. These two mag--nets, 28 and 63 are jointly called a duplex magnet 28--63.

As instanced in Fig. 3, the dynamo current coming to 40, over G7 follows39, Lil, (39 past junction 83, and coil 28 to the service main 59.rl`his also practically cuts out coil 63 without the use of arcingcontacts. This figure shows the junction S3 in advance of the coil .2863instead ot' at 4S, beyond the coils as shown in Fig. 6. The initialenergizing circuit for coil 63, tree from all the other circuits isshown in Fig. 3 by dotted arrows. The pig-tail 32 remains in permanentconnection with the bar 39 regardless'of the position of the bar.

1What I claim is-- l. In combination with a gas engine operatedgenerator, a storage battery and service mains, a control switch havinga line winding in circuit with the battery and the mains in order to beenergized by a service demand, an engine ignition means in a circuitcontrolled by the control switch, a starting switch having a winding ina circuit also controlled by the control switch, a governor operatedswitch included in the last mentioned circuit, a motor circuit includingthe battery and the generator as a motor and controlled by the motorstarting switch,

a main switch having a winding connected in circuit with the generatorand energized when the generator is driven by the engine, said controlswitch having a. coarse wire winding in circuit with the mains and thegenerator and controlled by the main switch, said main switch havinganvinterlock included in the starting switch winding circuit, and acharging resistance in circuit with the battery and the generator andcontrolled the main switch.

2. ln combination with a gas englnc operated generator, a storagebattery and service mains, a control switch having a line winding incircuit with the battery and the mains in order to be energized by aservice demand, an engine ignition means in a circuit controlled by thecontrol switch, a starting switch having a winding' in a circuil alsocontrolled by the control switch, a governor operated switch included inthe last mentioned circuit, a motor circuit including the battery andthe generator as a motor and controlled by the motor starting switch, amain switch having a winding connected in circuit with the generator andenergized when the generator is driven by the engine, said controlswitch having a coarse wire winding in circuit with the mains and thegenerator and controlled by the main switch, said main switch having aninterlock included in the starting switch winding circuit, and acharging circuit controlled by the main switch and including the batteryand the generator.

3. ln combination with a gas engine operated generator, a storagebattery and service mains, a control switch having a line winding in.circuit with the battery and the mains in order to be energized by aservici` demand, an engine ignition means in a circuit controlled by thecontrol switch, a starting switch having a winding in a circuit alsocontrolled by the control switch, a governor operated switch included inthe last mentioned circuit, a motor circuit including thebattery and thegenerator' as a motor and controlled by the motor starting switch, and amain switch having a winding connected in circuit with the generator andenergized when the generator is driven by the engine, said controlswitch having a coarse wire winding in circuit with the mains and thegenerator and controlled by the main switch, said main switch haring aninterlock included in the starting switch winding circuit.

4. In combination with a gas engine operated generator. a storagebattery and service mains, a control switch having a fine winding incircuit with the battery and the mains in order to be energized by aservice demand, an engine ignition means in a circuit controlled by thecontrol switch, a starting switch having a winding in a circuit alsoated generator, a storage battery and service mains, a control switch,having a tine winding in circuit with the battery and Athe nia-Ins inorder to be energized by a service demand, an engine ignition meansin acircuit controlled by the control switch, a starting switch having awinding in a circuit also controlled bythe control switch, a motorcircuit including the batteryand the genera; tor as a motor andcontrolled by the motor starting switch, and a main switch having awinding connected in circuit `with the generator and energized when thegenerator is driven bythe engine, said control switch having a coarsewire winding in circuit with the mains and the generator and controlledby the main switch said main switch having an interlock included in thestarting switch winding circuit.

6. In combination'with a gas engine oper-l ated compound wound generatorand-storage battery and service mains a control switchV havingavfmewinding in circuit withthe bat` tery and the mains 1n order to beenergized by a service demand, anengine ignition means in a circuitcontrolled by the control switch, a starting switch having a winding ina circuit also controlled by the control switch, aT

governor `operated switch. included in the last mentioned circuit, astarting circuit including the battery and the armature and shunt yfieldwinding of .the generator for operating the generator as a motor andconf trolled by the motor starting switch, a main switch having awinding connected in circuit with the armature and series field windingof the generator and energized when the generator is driven by theengine, saidy Icontrol switch having a coarse wire winding in fcircuitwith themains and thearmature and series field winding o the generatorand con- ,trolled by the main switch, said main switch also having aninterlocli included in the p starting switch winding circuit, and achargy.

ing reslstance in circuit with the battery-and the armature and seriesfield winding of the generator and controlled by the main switch.

7. *In automatic control switches for gas engine operated generatorplants. a conti-ol switch Serving both as a starting and runningcontrol, a battery supplying initial current to the control switchmagnet, a starting switch set into operation by the control switch, asupplemental governor control for the starting switch magnet, an engine`ignition circuit made operative and inoperative by the control switch,a main switch, a generator connected to the magnet thereof, servicemains supplied by' the generator,

.means controlled b y the main switch to maintain the control switch inoperated position so long as current is delivered to the sei'vice mainsby the generator and means operated by the main switch to cause thebattery to be charged from the generator.

8. In combination with a gas engine operated generatory and its mains,a'control switch serving both as a starting and runningk control abattery supplying initial current to the control switch magnet throughthe mains, a starting switch set into operation by the control switch aSupplemental governor control for the starting switch,an

engine ignition circuit made operative and inoperative by the controlswitch a main switch, thev generator being connected to the magnetthereof and connected to the senvice mains throughthe main' switch,ymeans controlled by the main switch towmaintain the control switch inoperated position so long as current is delivered to the service mainsby the generator, and means operated by the main switch to cause thebattery to be chargred from the generator.

j 9. .n combination with a gas operated generator and its mains, acontrol, switch lserving both as a starting and running control, abattery supplying initial current tc the control switch magnet throughthe mainsl a starting switch set'into operation Vby the control switch,`a supplemental governor control for the starting switch, an engineignition circuit made operative and inoperative by the controlswitch, amain switch,

the generator being connected to themagnet thereof and connected to theservice mains through the main switch, andv means controlled by themainvswitch to maintain the control switch in operated positionso longas current isdelivered mains by the generator. A

n In testimony whereof I affix il 5 WILLIAM to the service.

